- Mix water, sponge, sugar and flour (with the dough hook) on low for 4 minutes. - Dough will be wet and shaggy and will not clear the sides of the bowl.- Cover and rest 20 minutes.- Add salt and mix on medium for 5 minutes. - Add walnut oil.- Mix on low for 2 minutes or to an internal temperature of 65 F (18 C).- Add the roasted walnuts and mix on low until incorporated, about 2 minutes more.- Remove the dough from the bowl and knead by hand for a few minutes.- Lightly oil a bowl.- Form the dough into a boule, place in oiled bowl, cover tightly, and refrigerate for 8 to 12 hours.

If mixing by hand:

- Mix water, sponge, sugar and flour in a large bowl and mix by hand (with a large spoon) until all ingredients are combined.- Dough will be wet and shaggy and will not clear the sides of the bowl.- Cover and rest 20 minutes.- Add salt.- Knead by hand for 1 minute. Rest for 10. (Wet hands if dough is too sticky).- Knead by hand for 1 minute. Rest for 10. - Knead by hand for 1 minute. Rest for 10.- Add walnut oil.- Mix until dough reaches an internal temperature of 65 F (18 C) and/or is fully developed. Dough will be tacky, but not sticky.- Add roasted walnuts and mix until fully incorporated.- Remove dough from bowl and knead by hand for a few minutes more.- Lightly oil a bowl.- Form dough into a boule, place in oiled bowl, cover tightly, and refrigerate for 8 to 12 hours.

- Remove dough from refrigerator. It should have doubled in size. If not, cover dough and leave it at room temperature until it has.

- Turn dough out onto a lightly floured work surface.- Cut into two equal-sized pieces (~1100 grams each).- Form each into a rough boule and rest for 15 minutes.

- Form each into a tight boule.- Place each boule, smooth side down, into floured proofing baskets.- Sprinkle each with flour.- Cover and proof until it's 1.5x its original size (or to an internal temperature of 62 F (17 C)), about 2.5 hours.

- When loaves are fully proofed, lightly dust them with flour and carefully flip them onto a baker's peel.- Score with a sharp razor or baker's lame in a reverse 'C' pattern about 1/2 inch deep (13 millimeters) deep.

- Place loaves in oven.- Reduce oven temperature to 450 F (232 C).- Check loaves after 20 minutes. If baking unevenly, rotate. Remove steam pans.- Continue baking for 20 to 25 minutes more, for a total of 40 to 45 minutes.- Remove loaves and cool on wire rack.- Crust should be nut brown, with a nut brown interior.

IMAGES.

(These photos are from a 2010 bake. I may have posted a few of these before. Sorry if I did!).